Abstract
This paper introduces a technique for resolving amino acids that combines the advantages of the conventional CSP (chiral stationary phase) method with the CMPA (chiral mobile phase additive) method. A commercially available chiral crown ether column, CROWNPAK CR(+), was used as the CSP and three cyclodextrins (β- CD, γ-CD, HP-β-CD) were used as the mobile phase additives. Chromatographic resolution was performed at 25 °C and 50 °C with or without sonication. A comparison of the chromatographic results under ultrasonic conditions with those under non-ultrasonic conditions showed that ultrasound decreased the elution time and enantioselectivity at all temperatures. In the case of the β-CD mobile phase additive, the elution time and enantioselectivity under ultrasonic condition were significantly higher than under non-sonic condition at all temperatures. Commercially available Chiralpak AD, Whelk-O2 and Pirkle 1-J columns were used as CSPs to examine more meticulously the effects of ultrasonication and temperature on the optical resolution. The optical resolution of some chiral samples analyzed at 25 °C and 50 °C with or without sonication was compared. As in the previous case, the enantioselectivity was lower at 25 °C but similar enantioselectivity was observed at 50 °C.
Original language | English |
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Pages (from-to) | 4141-4144 |
Number of pages | 4 |
Journal | Bulletin of the Korean Chemical Society |
Volume | 33 |
Issue number | 12 |
DOIs | |
State | Published - 20 Dec 2012 |
Keywords
- Chiral stationary phase
- Enantioselectivity
- Mobile phase additive
- Temperature
- Ultrasound